9th Sentinel Sisters

Released: Sep 10, 2025
Platforms
Last updated: 14 Sep 2026, 01:08 GMT

Updates & announcements

9 posts

17 Dec 2025Developer post
Patch Notes (Ver 1.2.0)
Thank you for playing "9th Sentinel Sisters." This update introduces new features including dashing, skills, and attributes. We hope you continue to enjoy "9th Sentinel Sisters." Introducing New Features Battle Added Dash High-speed movement to evade enemies Added skills for each
Thank you for playing "9th Sentinel Sisters."
This update introduces new features including dashing, skills, and attributes.
We hope you continue to enjoy "9th Sentinel Sisters."
Introducing New Features
Battle
Added Dash
High-speed movement to evade enemies
Added skills for each character
Two types: passive skills that activate automatically, and active skills that can be triggered at any time
Passive Skills
Accelerator (Saika): Increases dash count
Bomber (Nina): Defeated enemies occasionally explode
Spike (Tetra): Knocks back enemies at the dash landing point
Active Skills
Deadly (Yayoi): Fires an enhanced New Wave
Limit Boost (Fem): Guarantees critical hits for a set duration and increases movement speed
Doom (Rei): Forces reload, shortens weapon reload time for a set duration
Added Attributes to Weapons
Three types: Bullet-type, Energy-type, Physical/Explosive-type
Added new parts corresponding to the new attributes
Added self-destructing enemies
Improved Game Experience
Changed the map confirmation screen to display tile descriptions when hovering the cursor over a tile
Other
Added various texts
Minor bug fixes
Original post
16 Oct 2025Developer post
Patch Notes (Ver 1.1.2)
Thank you for playing "9th Sentinel Sisters." We have fixed the issues that occurred in Version 1.1.1. We hope you continue to enjoy "9th Sentinel Sisters." Fixed an issue where clicking “Back” in the communication log did not respond when using keyboard/mouse controls.
Thank you for playing "9th Sentinel Sisters."
We have fixed the issues that occurred in Version 1.1.1.
We hope you continue to enjoy "9th Sentinel Sisters."
Fixed an issue where clicking “Back” in the communication log did not respond when using keyboard/mouse controls.
Original post
09 Oct 2025Developer post
Patch Notes (Ver 1.1.1)
Thank you for playing "9th Sentinel Sisters." We have fixed the issues that occurred in Version 1.1.0. We hope you continue to enjoy "9th Sentinel Sisters." Fixed an issue where the initial setting for left-click behavior was incorrect. Fixed other minor bugs.
Thank you for playing "9th Sentinel Sisters."
We have fixed the issues that occurred in Version 1.1.0.
We hope you continue to enjoy "9th Sentinel Sisters."
Fixed an issue where the initial setting for left-click behavior was incorrect.
Fixed other minor bugs.
Original post
07 Oct 2025Developer post
Patch Notes (Ver 1.1.0)
Thank you for playing "9th Sentinel Sisters." This update primarily focuses on adding new features and improvements to enhance gameplay. We will continue to develop various improvements and new features for future updates, aiming for releases throughout 2025. Further details on u
Thank you for playing "9th Sentinel Sisters."
This update primarily focuses on adding new features and improvements to enhance gameplay.
We will continue to develop various improvements and new features for future updates, aiming for releases throughout 2025.
Further details on updates will be announced in future patch notes.
Thank you for your continued support of "9th Sentinel Sisters."
Introducing New Features and Improvements:
Enhanced Conversation Features
Added a conversation log feature.
Added auto-advance functionality for conversation scenes.
Improved display of item effects during battle.
Improved Game Experience
Added a visual effect where the UI color changes when 10 seconds remain on the timer.
Added an instant retry function for game over.
Visualized weapon cooldowns.
Implemented unlock notifications.
Improved Operability
Options and other UI elements can now be operated with the mouse cursor.
Added a feature to check the map after selecting a square.
Enabled checking equipped parts when opening supply boxes.
Content Additions & Revisions
Introduced "How to Play" and "Customization" tutorials.
Added initial weapon level +1 to the 5th stage effect of weapon modification.
Added feedback effects to "Breakthrough" and other customization options.
Enabled detailed build configuration checks on the result screen.
Original post
13 Sep 2025Developer post
Regarding the Next Update
Based on your feedback, we are actively working on new features and improvements for 9th Sentinel Sisters . We’re aiming to deliver the following updates by the end of 2025 ! Planned Features & Improvements Please note: all items are currently under development and may be sub
Based on your feedback, we are actively working on new features and improvements for 9th Sentinel Sisters.
We’re aiming to deliver the following updates by the end of 2025!
Planned Features & Improvements
Please note: all items are currently under development and may be subject to change.
Conversation Enhancements
Add a conversation log feature
Auto-progress through dialogue scenes
Improve visibility of item effects during battle
Game Experience
UI color change alert when 10 seconds remain
Instant retry option after Game Over
Visual cooldown indicators for weapons
Unlock notification implementation
Usability Improvements
Enable mouse cursor navigation in UI/menus
Map preview after selecting a tile
Display held parts when opening a supply box
Content & System Enhancements
Add a tutorial for the “Customization” system
Add visual feedback for “Aggressive Advance” in customization
Allow build details to be reviewed on the result screen
This roadmap is based on our current development schedule, and specific release dates may change.
Further updates will be shared in upcoming patch notes.
Thank you for your continued support!
Original post
11 Sep 2025Developer post
9th Sentinel Sisters — Official Release Announcement
Thank you for supporting 9th Sentinel Sisters. We sincerely apologize for the lack of updates since the Early Access launch in October 2023. We are deeply grateful to everyone who has continued to support us throughout that time. With today’s update, we’ve significantly expanded
Thank you for supporting 9th Sentinel Sisters.
We sincerely apologize for the lack of updates since the Early Access launch in October 2023.
We are deeply grateful to everyone who has continued to support us throughout that time.
With today’s update, we’ve significantly expanded the overall game content and added several new features.
Players who purchased the Early Access version can update to the full version free of charge.
We hope you continue to enjoy 9th Sentinel Sisters—the journey is just beginning.
▼ Additions and Changes Since Early Access
Characters

Three new characters—Nina, Tetra, and Ray—have been added.
A new "Talk" feature is now available on the map, allowing character conversations and events to occur.
Your ending will now change depending on which character you used to clear the final missions.
Combat

Certain enemies now drop items upon defeat.
Epic boss battles against powerful Breed enemies have been added at the end of certain operations.
Operations

Several new operations have been added.
A Shop has been added to the map, allowing you to trade junk for equipment.
A new "VR Simulation" feature lets you rematch enhanced bosses after clearing boss missions.
Other Updates

UI improvements
Combat balance adjustments
Graphic enhancements
Original post
26 Dec 2023Developer post
Patch Notes（0.5.0）
Thank you for your interest in Early Access. Thank you also for the numerous feedbacks. Our development team is working hard to prepare for the official release. We look forward to your continued support of 9th Sentinel Sisters. Player Removed the limit on the number of parts you
Thank you for your interest in Early Access.
Thank you also for the numerous feedbacks.
Our development team is working hard to prepare for the official release.
We look forward to your continued support of 9th Sentinel Sisters.
Player

Removed the limit on the number of parts you can have and made all parts available.
Various statuses are now displayed in the pause menu during operations.
Changed the appearance rate and calculation method of upgrades that appear when leveling up.
Changed the calculation method of criticality correction and defensive strength.
Changed the method of counting the number of times of resurrection.
Adjusted the method of drawing lots for upgrade choices drawn at level-up.
UI

Changed the font size and color of the damage indicator when a critical hit occurs.
Added images to some items in the manual.
Operations

Adjusted the effect of events that occur in trace reactions.
Weapons and parts can now be obtained before the start of combat in enemy reactions.
Weapons and parts can now be acquired and recovered before the start of a threat enemy reaction.
Blue and red boxes are now guaranteed to appear in supply box reactions.
Increased the probability of the Golden Supply Box appearing in the supply box reaction.
Adjusted the number of encryption keys required to open each supply box.
Adjusted the number of times a supply box can be opened.
Adjusted the HP and knockback values of enemies that come at the player quickly.
Weapons, parts, modifications

Damage of bazookas, iai blades, and plasma cannons have been adjusted.
Maximum levels and effects of parts have been adjusted overall.
Effects of drill level-up have been adjusted.
Overall effects of modifications have been adjusted.
Original post
08 Nov 2023Developer post
Steam Deck verified
Passed Deck compatibility testing process “9th Sentinel Sisters” is now officially compatible with Steam Deck! Wherever you like, such as on the go Enjoy 9th Sentinel Sisters. We will continue to provide updates. Thank you very much
27 Oct 2023Developer post
Patch Notes（Rev 2890）
Thank you for your interest in Early Access. This mini-update mainly improves the tempo and difficulty of the early stages of the game, as well as the playing environment. Player The initial movement speed of the player's ship has been increased. Reduced experience required to le
Thank you for your interest in Early Access.
This mini-update mainly improves the tempo and difficulty of the early stages of the game, as well as the playing environment.
Player

The initial movement speed of the player's ship has been increased.
Reduced experience required to level up.
Battle and enemy

Reduced the time limit for battles caused by enemy reactions in the early to mid stages of the operation.
Shortened the time limit for Threatening Enemy Reaction battles.
Adjustments have been made to ease the appearance pattern and number of enemy appearances in battles in the early to mid stages of the operation.
The movement speed of enemies moving at high speed has been slowed down.
Graphics

Aim guides indicating the direction of fire are now displayed around your ship.
Adjusted the background of battles caused by Threatening Enemy Reaction.
The UI of the rank-up button in aircraft and weapon modifications has been adjusted.
Added optional items

Added an item for adjusting the dead zone when using the gamepad in the options.
Bug fixes

Fixed typos in the Iai blade description text.
Original post

Updates & announcements

Introducing New Features

Battle

Passive Skills

Active Skills

Improved Game Experience

Other

Introducing New Features and Improvements:

Enhanced Conversation Features

Improved Game Experience

Improved Operability

Content Additions & Revisions

Planned Features & Improvements

▼ Additions and Changes Since Early Access

Characters

Combat

Operations

Other Updates

Player

UI

Operations

Weapons, parts, modifications

Player

Battle and enemy

Graphics

Added optional items

Bug fixes